Utilization of the Under-Ice Habitat by Arctic Cod in the Western Arctic Ocean: A Multidisciplinary Collaborative Study

Arctic cod (Boreogadus saida), a key forage fish in the Arctic, may be particularly susceptible to changing sea ice conditions because they often form close associations with sea ice. This study examined the use of newly formed sea ice in the Chukchi and Beaufort seas by Arctic cod during the fall of 2019, assessed their abundance and body condition, and quantified the abundance of potential zooplankton prey in the water column below the sea ice. We found that Arctic cod were widely distributed along the Chukchi and Beaufort slopes at the ice-water interface and in several layers within the water column (as inferred from acoustic backscatter). Arctic cod were feeding on copepods and other zooplankton found in low to moderate abundances in the upper water column and on sea ice-associated zooplankton but Arctic cod sampled at the ice-water interface were in poor energetic condition with lipid levels that are associated with starvation in the laboratory.

2019-08-30 → 2023-01-31